Field of the Invention
The present invention relates to an image forming apparatus and a sheet conveying unit.
Description of the Related Art
Image forming apparatuses are configured to supply sheets one by one from a sheet feed tray, in which sheets are stacked, to an image forming unit, and after forming images on the sheets on the basis of an input image signal at the image forming unit, to discharge the sheets out of the apparatus. One example of such image forming apparatuses has a configuration having the function of reversing a sheet in which an image is formed on one surface (a first surface), conveying the sheet again to the image forming unit, and forming an image on an opposite surface (a second surface) of the sheet (double-sided printing).
Japanese Patent Laid-Open No. 2008-162744 discloses a configuration having a discharge pair of rollers for discharging sheets and a reversing pair of rollers for reversing the sheets. The configuration disclosed in Japanese Patent Laid-Open No. 2008-162744 adopts a switch back system for reversing sheets by rotating the reversing pair of rollers forward and backward.
However, Japanese Patent Laid-Open No 2008-162744 does not disclose a configuration for holding the discharge pair of rollers and the reversing pair of rollers. A configuration having a member for holding the discharge pair of rollers and a member for holding the reversing pair of rollers leads to an increase in the number of components or the size of the apparatus. Another conceivable configuration is such that two rollers are held by a single holding member. In this case, the holding member can be deformed in a longitudinal direction when subjected to nipping pressure (stress) from one direction.